The invention relates to a pressure control device for vehicles comprising a control device, a mechanical, pneumatic and/or hydraulic element and at least one sensor and/or an actuator.
Such pressure control devices are provided for use in pressure medium systems of, among others, vehicles. These may be constructed as pneumatic or hydraulic systems, in which case brake systems, level control systems, etc. are supplied by means of these systems.
German patent document DE-A-44 45 125 discloses a housing for an electric component, which housing consists of a housing bottom part and a housing top part. These parts can be connected with one another. In addition, a support is known from this document which supports the electric component situated in the housing and has corresponding electric connecting devices for the sealed connection of the electric component situated in the housing with an electric component situated outside the housing. Although such an arrangement has advantages in a modular construction, it is very time-consuming to assemble it with additional components, such as sensors and actuators. Also, additional, relatively long cables for connecting the sensors and actuators with the control device as well as additional housings for the sensors and actuators are required for protection against environmental influences. In addition, high-expenditure wirings and measures have to be carried out in order to protect the known control device against line-borne interferences of the additional cables.
It is therefore an object of the present invention to provide a pressure control unit with a control device, a mechanical, pneumatic and/or hydraulic element and at least one sensor and/or an actuator. The connection of the control device with the sensors, actuators and additional elements requires only a small amount of material, permits fast assembly and therefore saves time and cost.
This object is achieved in that a known pressure control device is further developed so that, in the area of the sensors and/or actuators, recesses or holes are provided in the control device and/or the mechanical, pneumatic and/or hydraulic element, in which the sensors and/or actuators can be at least partially accommodated.
The reason is that, as a result of this measure according to the invention, the mechanical, pneumatic and/or hydraulic element is moved into the direct proximity of the control device, so that the cable lengths can be kept short. Because of the measure that the mechanical, pneumatic and/or hydraulic element comprises a pressure control device, the assembly time is also reduced because now only one component or the pressure control device has to be mounted on the vehicle essentially by itself and not, as previously, at least two components with an additional mounting of other cables. As a result, material costs are also saved because only few casing parts are required for protecting the respective components from environmental influences.
When, preferably, at least one sensor and/or an actuator is arranged in the casing, it is possible to calibrate and test the control device with the sensors and/or actuators as a simple structural component. When, preferably in the area of the sensors and/or actuators, recesses or holes are provided in the mechanical and/or pneumatic and/or hydraulic element and/or in the control device, the sensors and/or actuators can be moved into the direct proximity of the components of the control device, so that long cable lengths can be avoided. The holes or recesses are preferably constructed on mutually facing sides of the element and of the control device.
The control device used according to the invention is an electric and/or mechanical control device. The control device preferably comprises a printed circuit board which is provided with recesses or holes for the sensors and/or actuators. In this manner, an even more compact construction can be obtained which can be mounted more rapidly.
Also preferably, the pressure control device comprises a casing having a first and a second casing part, the casing parts being mutually connectible. The first casing part together with the second casing part for at least the control device forms an essentially closed chamber. This measure permits a simple mounting and, in addition, a simple protection against environmental influences for the control device and additional components, such as in particular electric components.
The connectibility of the first and second casing part is preferably detachable in a firm manner. According to the field of application, seals are provided which protect the casing interior against water, dirt or the like. Furthermore, connections of a mechanical or electrical nature are preferably provided which have the effect that the interior area of the casing can be connected with the exterior area.
The mechanical, pneumatic and/or hydraulic element is preferably the second casing part. Further material can be saved as a result of this measure.
The hydraulic element is preferably a valve block. In this manner, it is possible to use a valve block with the pertaining control device as a single structural component.
The second casing part is preferably a control valve block for the compressed-air system of a vehicle.
When a bending-resistant element is preferably provided, forces, which otherwise act upon the casing, can be compensated without damage to the casing or the control device.
The bending-resistant element is preferably a casing part. In addition, the bending-resistant element can preferably be connected with a casing part.
If the bending-resistant element is provided for absorbing the pressure forces of the sensors and/or actuators, the control device will be mechanically protected. If, for example, preferably the control device comprises a printed circuit board, as a result of the absorption of forces by the bending-resistant element, there will be no hairline cracks on the printed circuit board because the latter will not be bent as a result of the application of force to the bending-resistant element.
Preferably, the controlling and the signal processing of the sensors and/or actuators takes place in the control device.
At least one amplifier is preferably provided in the control device, which amplifier amplifies the signals of the sensors. An active and/or passive cooling of the amplifiers (or of corresponding power semiconductors) is preferably provided. This cooling preferably takes place by way of cooling sheets and a portion of the exterior part of the casing.
If the amplifiers are arranged preferably in the direct or indirect vicinity of the sensors, which can be assigned, the connections to the amplifiers can be kept short so that few outside interferences can enter these cables. If the electric connection between the sensor and the control device takes place at least partially by way of flexible lines or one flexible line, the sensors and actuators can be moved with respect to the control device while the connection to the control device would suffer no fatigue and would not be destroyed.
A storage element is preferably constructed in the pressure control device. Also preferably, the calibrating values of the sensors and/or actuators and/or regulating parameters or control parameters of the control device can be stored in the storage element. This measure has the advantage that no external storage elements are required so that additional longer cables are also avoided.
The sensors and/or actuators are preferably arranged in an area between the two casing parts. Also preferably, the sensors and/or actuators are held by the two casing parts. As a result of these measures, additional holding elements can preferably be saved and a mounting is correspondingly simplified.
If, preferably, at least one seal is provided which seals off the sensors and/or actuators, a discharge of pressure medium from the pressure medium outlet bore, for example, of a valve block, will be avoided. Depending on the embodiment of the present invention, different seals can be used which achieve the sealing in different fashions. The seal is preferably provided between the pressure connection of the second casing part and the sensor. As a result of this measure, only a single seal will be required. In addition, as a result of this measure, by means of the correspondingly firm or loose mounting of a component pressing onto the sensor, such as the first casing part or the bending-resistant element, the contact pressure onto the seal can be adapted according to the requirements or pressure conditions, the used material, the environmental influences and the like.
The sensor is preferably cup-shaped. Also preferably, the sensor is held or guided by way of the edge of the cup-bottom by a casing part. As a result of this measure, the cup-shaped sensors can be fitted well. In the event of corresponding pressure variations, these will not cause corresponding pressure medium leakages at this connection from the pressure medium to the control device.
When the sensor membrane is preferably constructed on the cup bottom, this membrane is protected from corresponding damage by a not quite appropriate mounting.
The invention will be described in the following as an example without any limitation of the general idea of the invention by means of embodiments with reference to the drawings, to which reference is also made with respect to the disclosure of all details according to the invention which are not explained in detail in the text.